This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Previous studies have shown that arenaviruses are pleiomorphic, with particles ranging from 400 to 2000 angstroms in diameter. Preliminary data suggested that Candid#1 viral particles are pleiomorphic by negative stain necessitating tomographic data collection/reconstruction. From our first attempts of cryoimaging of Candid#1 it looks like the virions have spikes arranged on their surface, most likely made from viral glycoproteins.